The use of multi-cavity molds such as those used in polymer injection molding machines is well known. Such machines utilize heated, liquefied plastic forced through each of the cavities in a mold until the cavities are filled. The liquefied plastic flows through conduits called runners that interconnect a plurality of parts within the mold. The plastic is then cooled to solidify and the remaining part and runner array is then ejected from the machine. In a preferred system, the part and runner are separated from each other automatically.
One problem existing in the industry is the separation of various parts in a multi-cavity mold system. While the same part may be produced from identical molds in a multi-cavity mold system, a heterocavity system utilizes a variety of different molds and a plurality of different products are ejected from the machine concurrently. Furthermore, it is often difficult to separate the differing mold products once they have been ejected.
Additionally, even if the same mold product is ejected from a plurality of cavities, it is desirable for quality control purposes to associate the mold output with a specific mold cavity in the event a defect in one or more of the cavities is discovered.
One method of separating and delivering mold parts, whether they are plastic or composed of other materials, is the use of compressed air to effectively propel the parts from their point of ejection to their point of collection. U.S. Pat. No. 3,163,470 to Brewin et al describes a pneumatic system to propel lightweight materials, such as hosiery, through a plurality of independent and separate channels to their intended location. The structure in this patent is not directed to receiving, stripping, ejection or other process for the separation of plastic parts from a runner assembly.
U.S. Pat. No. 3,986,811 to Gunnels, Jr. describes a molding apparatus with receiving chute device arranged below opposing plates of a mold machine whereby the molded product drops from the machine when the plates separate and means are provided to deflect the product and transport it for further processing.
U.S. Pat. No. 4,118,168 to Ress et al. describes a guidance system for substantially flat mold products discharged from a mold cavity whereby upon ejection from the mold plates, the products fall into a vertical channel maintaining a predetermined orientation for optimal collection and/or processing.
U.S. Pat. No. 4,608,008 to Hehl describes a compact parts discharge conveyor adapted for injection molding machines whereby mold products discharged from the molding machine fall from the plates onto a conveyor means comprising an endless conveyor belt rotatably mounted within a chassis, the chassis including a core disposed between the upper and lower belt runs of the conveyor belt. Two side walls secured to the longitudinal sides of the core retain the mold products traveling on the belt.
U.S. Pat. No. 4,719,059 to Braun et al. describes a material handling device whereby mold products ejected from an injection mold machine fall into a basket on rails which then moves on the rails to a location away from the mold for further processing.
U.S. Pat. No. 4,741,687 to Eltvedt describes a guide skirt for guiding parts ejected from an injection mold to a receptacle whereby the sides of the skirt are pivotably connected together so that the bottom outlet port also opens and closes as the mold plates move back and forth between open and closed positions.
U.S. Pat. No. 4,946,357 to Harrison describes a diverter chute assembly to automatically separate the molded part from the runner in injection mold machines. The assembly comprises a deflection plate pivotally mounted within a housing and responsive to control signals synchronized with the ejection of the mold product and the runner whereby the product is directed to a first collection area and the runner is directed to a second collection area.
U.S. Pat. No. 5,439,634 to North describes a method and device for separating runners and sprues from parts as they are ejected from an injection mold machine comprising a product receiver underlying the injection molds for receiving the product after the molds have been opened whereby
An apparatus described in U.S. Pat. No. 4,901,503 to Gomez et al. provides an assembly for the receiving of a plurality of interconnected plastic parts from a plastic mold through the provision of a collector means moveably mounted to travel on a base. The collector means includes a plurality of chambers proportional in number to the number of plastic parts being ejected from the mold such that each part of a given array of parts is received in an independent chamber. A plurality of individual tubes connect each independent chamber to a delivery point for the mold products. Compressed air is used to force the products through the individual tubes.
None of the systems described above provide a sorting mechanism that keeps different molded parts in the same mold from intermixing during a free fall into a collector. Furthermore, there is a need in the art for a faster and more efficient sorting mechanism for heterocavity mold systems that do not require robotics to collect the mold products from the machine for further processing.